Maesters

Maesters are an order of sholars and advisors to noble houses of Westeros. They train in a school called The Citadel and are individually assigned to a keep or holding. Like the Night's Watch, they are servants to the realm and take oaths for life. Stripping themselves of all allegiences and loyalties, they wear the chain of office. It is rumored Maesters hold much more power and influence over the realm's history than most think. Each Maester wears a chain that signifies that they do not serve themselves, but the realm, and each link of the chain represents an area of study the particular Maester has mastered. These links include:

Black Iron for Ravenry

Bronze for Astronomy

Copper for History

Gold for Economics

Iron for Warcraft

Pale Steel for Smithing

Silver for Medicine and Healing

Valyrian Steel for Magic

The study of magic is looked down upon by the maesters. Only one in 100 posseses a Valyrian Steel link.

Maester Luwin is a recipient of a Valyrian Steel link.

There's many maesters across all of Westeros, usually one or two for each region or holdfast, such as: